First time the car has seen measureable rain (more than just drizzle) and I get to work and i hear hissing from the exhaust and see some steam. So I look under the car and the connection from the headers to the cat is steaming pretty good. Is that a good sign that I have an exhaust leak there and need to tighten the bolts up? I've never seen/heard it do this before. Not sure if it is even anything to worry about.

 

So many views and no help? Is this a dumb question?

 

I don't think a hot spot in the exhaust is indicative of a leak. The cat gets extremely hot under normal driving conditions. That heat will transfer to the inlet and outlet piping. Anything near the cat will be several times the temperature required to boil water. The queston is was there still water dripping off the bottom of the chassis?

On the other hand, if exhaust way actually escaping on a cold/humid day, its conceivable that the moisture in the exhaust would condense and become visible, but that doesn't seem to be what you are describing.

Easy enough to check - first look for carbon tracking on the header flange (or slip fit connecton). Then let the engine idle and hold your hand near the connection and feel for exhaust squirting out of the flange. Have someone hold something over the exhaust tip(s) to raise the pressure in the exhaust and promote leakage at idle.

 

Yeah, there was still plenty of water under my car that could have easily been dripping onto that connection. I just thought it was funny that this was the only place that was doing this... everything else was wet, but not creating steam.

Ive tried the whole "put your hand over the exhaust" before to test for leaks, guess i can try that and just feel around in that area. Thanks... thought it was a little goofy that is all.

 

no exhaust leaking out that i could feel... tried tightening up the studs, and nodda... not sure why it was doing this.

 

If theres no leaks, you were probably just hearing water sizzle from the heat of the pipes. They can get pretty hot. If you notice your gas mileage dropping or something out of the ordinary while drving, then look into it more.

 

I worry more about the OPTI when my wife's 94 gets caught in the rain. These days she checks the forcast before driving...a little water throws on the SES and causes me to hook up the laptop. Gotta love the non-vented opti. Luckily, Florida provides many sunny days to drive